This invention relates to improvements in the structure of a framework for an inclined passenger conveyor, such as an escalator.
Conventional structures of a framework for a passenger conveyor have been disclosed, for example, in Japanese patent publication Nos. 49114/1976 and 48434/1981. One of those conventional structures comprises a lower framework constituted by a truss having a rectangular cross-section and made up of a plurality of steel bars and including a horizontal portion and an inclined portion connected to the horizontal portion by a bent part at a predetermined angle to the horizontal portion, an upper framework similar to the lower framework, and an intermediate or inclined framework constituted by a truss similar to that of each of the lower and upper frameworks and connected between the inclined portions of the lower and upper frameworks by respective angle splice members to form together with the inclined portions of the lower and upper frameworks, a rectilinear inclined portion of the structure.
In such conventional framework structures, each of the lower and upper frameworks has horizontal and inclined portions, which makes it difficult to assemble the respective trusses accurately. Also, it has been necessary for the welding operation to use complicated welding jigs, and it has been necessary to perform the operations at elevated positions, thus causing the manufacturing cost to be rather high. Furthermore the individual lower, upper and intermediate frameworks of such framework structures have generally been individually packed and conveyed to the building sites where they are assembled. It has been necessary to make the packings for the lower and upper frameworks large because of the presence of the inclined portions thereof. This has resulted in the disadvantages that the conveying cost is increased and, during their conveyance to the building sites, the packages for such frameworks require relatively large passageways to accommodate them. In addition, the package for the upper framework requires much labor to handle because a conveying skid must be placed thereunder to prevent the upper framework from being deformed due to its own weight.
Accordingly it is an object of the present invention to provide a new and improved framework structure for a passenger conveyor, which framework can be easily manufactured and readily conveyed to the desired building site.